Phosphonous acid monoester-monoamides

Abstract

Phosphonous acid monoester-monoamides of the formula ##STR1## in which n is 1 or 2, when n is 1, R 1 is alkyl or phenyl, or when n is 2, R 1 is phenylene-Y-phenylene where Y is a direct bond, --O--, --S-- or alkylidene, R 2 , R 3 and R 4 are independently hydrogen or alkyl and R 5 and R 6 together with the N-atom to which they are bonded from a heterocyclic ring, are suitable for protecting organic material from the harmful effect of heat, oxygen and light.

What is claimed is: 
     
       1. A compound of formula I ##STR22## in which n is 1, R 1  is phenyl, R 2  is hydrogen or C 1  -C 8  alkyl, R 3  is hydrogen or C 1  -C 8  alkyl, R 4  is hydrogen or C 1  -C 8  alkyl, and R 5  and R 6  together with the nitrogen atom to which they are attached represent a piperidine or hexamethyleneimine ring. 
     
     
       2. A compound according to claim 1 in which R 2  is C 4  -C 8  alkyl, and R 3  and R 4  are hydrogen or C 1  -C 8  alkyl. 
     
     
       3. The compound according to claim 1 which is phenylphosphonous acid mono-(2,4,6-tri-tert-butylphenyl)-ester monopiperidide. 
     
     
       4. The compound according to claim 1 which is phenylphosphonous acid mono-(2,6-di-tert-butylphenyl)-ester monopiperidide. 
     
     
       5. The compound according to claim 1 which is phenylphosphonous acid mono-(2,6-di-tert-butyl-4-methylphenyl)-ester monopiperidide. 
     
     
       6. The compound according to claim 1 which is phenylphosphonous acid mono-(2,4-di-tert-butylphenyl)-ester monopiperidide. 
     
     
       7. The compound according to claim 1 which is phenylphosphonous acid mono-(2,6-di-tert-butyl-4-methylphenyl)-ester monohexamethyleneimide. 
     
     
       8. The compound which is ##STR23##